Combine harvesters are used to harvest crop on a field, such as wheat, oats, rye, barley, corn, sorghum, soybeans, sunflowers, canola, etc. After the threshing and separation process, a grain pan conveys the harvested crop to the next phase, for example the cleaning unit. This is usually achieved by shaking the grain pan. The grain pan may be part of a cleaning shoe.
Conventionally the grain pan is a welded steel construction with a thin steel plate. The grain pan is welded, usually spot welded, to the side beams. Under the steel plate cross profiles provide additional support. This conventional design suffers from vulnerabilities with regards to fatigue. Due to the high cycle loads the grain pan is exposed to, failure is a frequently occurring issue. In case of failure, the entire grain pan needs to be replaced, often together with the side beams.
Between the grain pan and the side beams, gaps are present in the conventional design. Deformation of the various parts due to the high cycle loads causes said gaps to grow. These gaps form so called grain leaks, since crop falls through these gaps. This results not only in loss of product, but as well in crop being stuck in undesired places, e.g. between the thin steel plate and the side beams and/or the cross profiles.
The object of the present invention is to provide an improved grain pan.